Tilman Tröster

CFHTLenS and RCSLenS Cross-Correlation with Planck Lensing Detected in Fourier and Configuration Space

We measure the cross-correlation signature between the Planck cosmicmicrowave background (CMB) lensing map and the weak lensing observations from both the Red-sequence Cluster Lensing Survey and the Canada-France-Hawaii Telescope Lensing Survey. In addition to a Fourier analysis, we include the first configuration-space detection, based on the estimators \textlesskappa(CMB)kappa(gal)\textgreater and \textlesskappa(CMB)gamma(t)\textgreater. Combining 747.2 deg(2) from both surveys, we find a detection significance that exceeds 4.2 sigma in both Fourier-and configuration-space analyses. Scaling the predictions by a free parameter A, we obtain A(CFHT)(Planck) = 0.68 +/- 0.31 and A(RCS)(Planck) = 1.31 +/- 0.33. In preparation for the next generation of measurements similar to these, we quantify the impact of different analysis choices on these results. First, since none of these estimators probes the exact same dynamical range, we improve our detection by combining them. Secondly, we carry out a detailed investigation on the effect of apodization, zero-padding and mask multiplication, validated on a suite of high-resolution simulations, and find that the latter produces the largest systematic bias in the cosmological interpretation. Finally, we show that residual contamination from intrinsic alignment and the effect of photometric redshift error are both largely degenerate with the characteristic signal from massive neutrinos, however the signature of baryon feedback might be easier to distinguish. The three lensing data sets are publicly available.

Cross-correlating Planck tSZ with RCSLenS weak lensing: implications for cosmology and AGN feedback

We present measurements of the spatial mapping between (hot) baryons and the total matter in the Universe, via the cross-correlation between the thermal Sunyaev–Zeldovich (tSZ)map from Planck and the weak gravitational lensing maps from theRed Cluster Sequence Lensing Survey (RCSLenS). The cross-correlations are performed on the map level where all the sources (including diffuse intergalactic gas) contribute to the signal. We consider two configurationspace correlation function estimators, ξ y–κ and ξ y–γt , and a Fourier-space estimator, Cy–κ , in our analysis. We detect a significant correlation out to 3◦ of angular separation on the sky. Based on statistical noise only, we can report 13σ and 17σ detections of the cross-correlation using the configuration-space y–κ and y–γ t estimators, respectively. Including a heuristic estimate of the sampling variance yields a detection significance of 7σ and 8σ, respectively. A similar level of detection is obtained from the Fourier-space estimator, Cy–κ . As each estimator probes different dynamical ranges, their combination improves the significance of the detection. We compare our measurements with predictions from the cosmo-OverWhelmingly Large Simulations suite of cosmological hydrodynamical simulations, where different galactic feedback models are implemented. We find that a model with considerable active galactic nuclei (AGN) feedback that removes large quantities of hot gas from galaxy groups and Wilkinson Microwave Anisotropy Probe 7-yr best-fitting cosmological parameters provides the bestmatch to the measurements. All baryonic models in the context of a Planck cosmology overpredict the observed signal. Similar cosmological conclusions are drawn when we employ a halo model with the observed ‘universal’ pressure profile.

KiDS-450 : tomographic cross-correlation of galaxy shear with Planck lensing

We present the tomographic cross-correlation between galaxy lensing measured in the Kilo Degree Survey (KiDS-450) with overlapping lensing measurements of the cosmic microwave background (CMB), as detected by Planck 2015. We compare our joint probe measurement to the theoretical expectation for a flat

Cross-correlation of weak lensing and gamma rays : implications for the nature of dark matter

\Lambda

Cosmological simulations for combined-probe analyses: covariance and neighbour-exclusion bias

CDM cosmology, assuming the best-fitting cosmological parameters from the KiDS-450 cosmic shear and Planck CMB analyses. We find that our results are consistent within

Weak lensing corrections to tSZ-lensing cross correlation

1\sigma

A Search for Warm/Hot Gas Filaments Between Pairs of SDSS Luminous Red Galaxies

with the KiDS-450 cosmology, with an amplitude re-scaling parameter

Multi-wavelength scaling relations in galaxy groups: a detailed comparison of GAMA and KiDS observations to BAHAMAS simulations

A_{\rm KiDS} = 0.86 \pm 0.19

KiDS-450: enhancing cosmic shear with clipping transformations

. Adopting a Planck cosmology, we find our results are consistent within

A Bayesian quantification of consistency in correlated datasets.

2\sigma